Heel-trimming machine



(No Model.) E.

, C. W. GLIDDEN.

HEEL TRIMMING MACHINE.

Patejnted NOV. 20, 1888.

. SIZE=- N PETERS, Phnmuthognpher, wnmngcan. D. C.

STATES Armar erica..

V. ...1 *hmmm ...H

CHARLES W. GLIDDEN, OF LYNN, ASSIGNOR TO JAMES \V.'BROOKS, TRUSTEE, OFCAMBRIDGE, MASSACHUSETTS.

HEEL-TRIMIVIING MACHINE.

SPECIFICATION forming part of Letters Patent No. 393,103, datedNovember 20, 1888. Application nica May caisse. saranno. amata (No meel.)

To all whom it may concern.-

Be it known that I, CHARLES W. GLrDDEN, of Lynn, county of Essex, State of Massachusetts, have invented an Improvement in Heel- Trimming Tools, of which thc following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

This invention is an improvement on that class of tools having a series of blades pivoted at their inner ends and co-operating with a rand-guide having a lip or flange to arrest the outer ends of the blades, so that their cuttingedges face in the same circle, myipresent invention being an improvement upon that described in application Serial No. 268,851, filed March 29, 1888, wherein the pins or pivots about which the heels of the blades turn are so held in the hub as to always occupy a position at the same distance from the center of rotationof the cutting-tool. Blades of this kind when made are shaped externally to give to them such curvature as shall afford just the right amount of clearance The blades referred to in use become dul'led and are frequently ground, cach grinding shortening the blades,so that when again applied to the tool the blades occn py cach time a more nearly radial position, and with cach shorten ing of the blades by grinding the clearance is also altered by reason of the different angle assn med by the blades. 1t is a great desideratum to maintain the clearance the same under all conditions, and to do this I have mounted the near or inner ends of the blades or pivots, which are made movable toward and from the center of rotation of the tool, so that as the blades are shortened by grinding the pivots on which the blades turn may be moved away from the said center sufficiently to compensate for the shortening of the blades.

My invention in rotary tools for trimming heels consists, essentially,in a hub and a randguide having alip to arrest the outward movement of the free ends of the blades, combined with pivots for the said b1ades,which are made movable away from the center of rotation of the tool as the blades are shortened by grinding,to thus maintain the clearance of the blades uniform.

Figure 1 represents one of my`improvedA 2 amount of clearance.

tools with the rand-guard removed. Fig. 2 shows the inner side of the rand-guard removed from Fig. 1. Fig. 3 shows the entire tool in section on the line x, Fig. 1; and Fig. 4, a diagram, to illustrate my invention.

The shaft A-common to any heel-trimming machine-has mounted upon ita tread-guard, B,of usual construction. The shaft A,as shown, has two many-sided or other than cylindrical holdingsurfaces,a b, which receive upon them, respectively, the pivot-holding plate c and the rand-guide d, the plate c and rand-guide at their contiguous faces having respectively, as shown, three eccentric slots, 2 and 3. The holding-surfaces a b compel the parts c and d to rotate in unison with the shaft A.

The cylindrical portion e of the shaft A, between the holding-surfaces a b, receives upon it the hub or headf, having slots, as best shown inv Fig. 1, which slots receive the pins or pivots g, on which turn freely the inner ends of the blades h,the outer orv free ends of which when the tool is in operation rest against the lip or (iangc f1 of the rand-guide.

In Fig. 1 the blades are supposed tobe of full length, and the pins or pivots g bottom in the slots of the hub, and the arcs in which lie the backs 5 of the blades afford the proper Now, as the blades are shortened by grinding, they, if the pins or pivot-s q were always held at the same distance from the center of the shaft, would` eventually assume a posit-ion such as shown by the shortened blade, full lines, Fig. hwhen the clearance would be very different from that shown in Fig. 1. To overcome this the ends of the pins or pivots g enter the eccentric slots or cam-surfaces 2 and 3, and when the blades are ground back and shortened the operator will change the relative position of the hub and shaft by holding one and turning the other slightly, which will cause the eccentric slots 2 and 8 to move the pins or pivots g out away from the center of rotation of the shaft A, thus keeping the clearance substan' tially the same under all changing conditions of the blades.

The dotted lines, Fig. et, show the shortened blade carried out at its pivoted end to maintain the clearance to the standard.

The washer m and nut a keep the rand- IOO guide, hub,and plate c on the shaft and clamp and in the slots 3 of the rand or counter guard, them together with such force that one cannot and a treadguard, the combination being and be rotated independently of the other except operating substantially as described. by loosening the nut. In testimony whereof I have signed my name r 5 5 I claim* `to this specification in the presence of two sub- The shaft A the slotted plate c,and the rand soribing Witnesses. or counter guard d, the latter slotted at 3 at its inner side,a,nd provided with a 1ip,4,@ombined CHARLES W' GLIDDEN' With the hub f, the blades 5, pivoted at their Witnesses: 1o heels upon pins g, resting in slots of the hub, GEO. W; HAMMATT,

the said pins entering the slots in the plate c H. P. FAIRFIELD. 

